Munich's beer gardens go back to the early 1800's, when King Ludwig I granted brewers the right to serve their product outdoors. In those days, it was against the law to brew during the warm months. So brewers prepared for the summer layoff by making extra-strong--and thus less perishable--beer in early spring. The beer was called Märzen, German for March.

Brewers had to contend with another problem: keeping the beer from getting warm. Because Munich had a high water table, they found it hard to store the brew underground. So they planted chestnut trees--which grew fast and provided lots of shade--and kept the beer beneath them. Today, you'll still find chestnut trees in just about every beer garden.

Beer gardens are Munich's "outdoor living rooms." They're places where people relax, soak up the sun, and enjoy the company of family and friends. Some offer traditional oompah music or Dixieland jazz, others are places for quiet conversation. While you must be 16 to drink, all ages are welcome; many beer gardens have large play areas, along with soft drinks, for children. On a bright Sunday, it's not unusual to see three generations spending the afternoon together.

Beer is served in glass one-liter steins, just like in the beer halls. The best-selling style is Helles, German for "light-colored"; it might look like American lager, but it's crisper and heartier. Also on tap is weizen (wheat beer), a perfect summertime drink; and dunkel, the dark-colored beer many Germans associate with Munich. Radler, a combination of lager and lemonade--an acquired taste for North Americans--is another beer garden favorite.

A trip to a beer garden isn't complete without something to eat. If you aren't hungry when you arrive, you'll soon succumb to the aroma of chicken and sausages on the grill. The bill of fare runs heavily toward Bavarian favorites: roasted pork knuckles; fresh radishes, which locals peel using a special tool; smoked mackerel on a stick; and Obatzer, a mixture of Camembert, onion, and paprika.

Although beer gardens serve food, bringing in one's own is a time-honored tradition, thanks again to King Ludwig. When the brewers asked him to ban food from outside, the king offered a compromise: customers could bring food in, but could only eat it at tables without a tablecloth. That's still the custom in beer gardens. So are shared tables: if you spot an empty place, ask whether it's occupied before sitting down.

An essential part of the beer garden ritual is packing a picnic hamper. Food tops the list, of course; favorites include black bread, cheese and sausage, radishes and cucumbers, tubes of mustard, and giant pretzels. Paper plates and plastic forks won't do; conservation-minded Münchners bring china and silver from home. A checked tablecloth, in Bavarian blue and white, is also a must. So are candles for those planning to stay after dark.

In Munich, you're never far from a beer garden. There are more than 150 in town, with room for well over 100,000. Here are a few of the best: